1. Field of the Invention
This invention relates generally to cotton cleaning devices, and particularly to a cotton cleaning machine mountable directly on a cotton gleaner or scraper for separating dirt and debris from scrap cotton gathered by the scraper.
2. Description of the Prior Art
Devices generally referred to as cotton gleaners or cotton scrapers are commonly employed to traverse ground between cotton plants in order to recover cotton from a field after normal picking procedures have been completed. Such a gleaner or scraper is disclosed in U.S. Pat. No. 2,670,584, issued Mar. 2, 1954 to W. E. Rood, Jr. et al. Basically, these cotton scrapers employ an endless belt conveyor which engages cotton on the ground as the belt passes over a lower pulley on which the belt is mounted, and carries the gathered cotton upwardly along the lower run of the belt. While the cotton thus gathered can be merely deposited in a bin adjacent the upper end of the run of the belt, generally a further arrangement is provided for taking the gathered cotton from the endless belt and transmitting the cotton to a further point for ultimate discharge from the scraper. This is accomplished in cotton scrapers made under U.S. Pat. No. 2,670,584 in several manners, with a model manufactured in approximately 1960 or 1961 employing a drag chain device to achieve such further conveyance. Models manufactured immediately after the drag chain model use additional series of belts, with perhaps three belts being employed in all, and the intake end of each subsequent, or downstream, belt being disposed beneath the discharge, or upper end, of the previous, or upstream, belt from which the particular belt receives the cotton. In this manner, each belt after the first, or gathering, belt carries the gathered cotton on the upper run thereof, instead of the lower run as in the case of the initial belt.
Around 1964 or 1965, a basket was attached to the then current model of these cotton scrapers for catching the cotton as it is discharged.
A difficulty encountered with the continued use of older models of the cotton scraper, and particularly those made under U.S. Pat. No. 2,670,584 during the years 1960 to 1965, is that current EPA requirements placed on the ginning of cotton have made it economically necessary that the cotton gathered by a cotton scraper be cleaned prior to insertion into the gin in order to reduce ginning costs and increase the growers net yield of cotton per acre, while complying with the increasingly stringent requirements imposed on ginning operations by the Federal Government.
It should also be mentioned that although in theory the cotton scrapers as discussed above will operate with only a single endless belt at each stage of the scraper, from gathering to discharge, in practice it has been found that a plurality of belts disposed in parallel advantageously form each stage of such scrapers. These parallel belts are spaced slightly from one another so as to form gaps between them.
Cotton is conventionally cleaned by the use of a sawtooth drum used in combination with a doffer which removes the clean cotton from the drum. Examples of such cleaners can be found in U.S. Pat. No. 3,528,138, issued Sept. 15, 1970 to R. L. Elder; U.S. Pat. No. 3,382,544, issued May 14, 1968 to F. A. Moore; and U.S. Pat. No. 3,150,417, issued Sept. 29, 1964 to H. C. Word. These known cleaners, however, are specifically intended for use on the discharge of a conventional cotton-picker, and are not suitable for use with a cotton scraper. Further, the devices set forth in the aforementioned prior patents rely on fluid pressure to feed cotton into them, which pressure is not available on a cotton scraper, and which pressure in any event tends to create uneven feed into the device, and generally make inefficient the operation of the cleaner.